weight: bold" lang=EN-US>Morphologic Characteristics of Yangjiao Basalt in the Middle Taihang Mountains and Their Geological Significance

• 责任者：Gong Mingquan (Institute of Geomechanics ; CAGS ; Beijing 100081 ; China) ; Ma Yinsheng
• 刊名：Acta Geoscientica Sinica
• 出版年：2010
• 卷期：31(1)
• 关键词：玄武岩 ; basalts ; 隆起 ; uplifts ; 太行山 ; Taihang Mountains
• 页码：p.56-64
• 图表：10 illlus., 1 plate, 14 refs.
• 分类号：0801
• issnNo：ISSN1006-3021
• isbnNo：CN11-3474/P

Based on field investigation, the authors studied the morphologic characteristics of the basalt and the related topographic surface, and detected that the basalt was formed between the end of Pliocene and the beginning of Early Pleistocene.  The geomorphic evolution of the middle Taihang Mountains since Late Pliocene is as follows: in Late Pliocene, this area underwent two phases of geomorphic evolution, i.e., uplift and erosion, and this led to the formation of the “U” valley; at the end of Pliocene, because of the repeated and intermittent eruption of the basalt and the uplift of the geomorphic surface of the middle Taihang Mountains centered at Wujiaping Village, the basalt filled the “U” valley, and then the geomorphic surface of the fourth terrace was formed through erosion and accumulation; in Early Pleistocene, the geomorphic surface of the middle Taihang Mountains was uplifted so that the fourth step terrace was formed.  At the end of Middle Pleistocene, the third terrace was formed; Since Late Pleistocene, two times of uplifting of the geomorphic surface took place, and hence all of the four steps of terraces came into being on the basalt.  It is shown that the uplift of the middle Taihang Mountains occurred mainly between the end of Pliocene and Early Pleistocene.  This cognition offers material evidence for the uplift of the middle Taihang Mountains since Late Pliocene.